JavaScript is a programming language that is one of the core technologies of the World Wide Web, alongside HTML and CSS. It is a scripting language that enables you to create dynamically updating content, control multimedia, animate images, and pretty much everything else. Here are some key features of JavaScript:

• Client-side scripting: JavaScript is the dominant client-side scripting language of the Web, with 98% of all websites using it for this purpose.

• High-level language: JavaScript is a high-level, often just-in-time compiled language that conforms to the ECMAScript standard. It has dynamic typing, prototype-based object-orientation, and first-class functions.

• Multi-paradigm: JavaScript is multi-paradigm, supporting event-driven, functional, and imperative programming styles.

• APIs: JavaScript has application programming interfaces (APIs) for working with text, dates, regular expressions, standard data structures, and the Document Object Model (DOM) .

JavaScript is used to make dynamic websites, web and mobile apps, games, web servers, back-end infrastructures, and more. It is most commonly used to create dynamic, interactive websites, and developers use it to add animations, pop-up windows, search bars, buttons, audio and video, chat widgets, and other interactive elements to a webpage.